Chinese shoppers spent a massive 35 billion yuan — that’s $5.7 billion — in an online shopping spree timed to coincide with the country’s Singles’ Day. That’s more than double what Americans spent on Cyber Monday last year and 80% over last year’s sales.

Observed each year on 11/11 — the lnumerals are said to resemble bare branches, a Chinese term for bachelors — Singles’ Day started in the 1990s as a kind of anti–Valentine’s Day, marked with dinner or drinks among unmarried friends. Over the past few years, online shopping giant Alibaba turned the wistful occasion into a bargain-hunting bonanza, capitalizing on young consumers with disposable income. In a country where males outnumber females by about 34 million, there are plenty of lonely hearts to go around. And they love to shop online.

This year on “Double 11,” Alibaba’s sites, led by Taobao and Tmall, received more than 400 million unique visitors as people logged on to scoop up everything from mobile phones to “boyfriend” pillows. One woman paid an $820,000 deposit for a 13.3-carat diamond ring worth $3.3 million, according to state media reports. Other purchases were more quotidian: Alibaba says it sold 2 million pairs of underwear and 1.6 million bras — all before lunchtime.

The success of this year’s Singles’ Day sale will no doubt bolster Alibaba, which is heading into a closely watched IPO. For China’s singles, tomorrow’s another day — to shop if not love.